Movable chair



June 1, 1965 R. L. PROPST 3,136,761

MOVABLE CHAIR Filed March 14, 1961 3 Sheets-Sheet 1 INV EN TOR. ROBE/77 Z. PROPS? R. L. PROPST MOVABLE CHAIR June 1, 1965 5 Sheets-Sheet 2 Filed March 14, 1961 A TTOR/VE Y5 R. L. PROPST MOVABLE CHAIR June 1, 1965 3 Sheets-Sheet Z5 Filed March 14, 1961 F. H HHH 9 9 0 3 0 m a 9 mm 2 o I m I 6 9 I F V 9 #05527 1. #20297 BY i INV EN TOR.

United States Patent 3,186,761 MOVABLE QHAIR Robert L. Propst, Ann Arbor, Mich, assignor to Herman Miller, Inc, a corporation of Michigan Filed Mar. 14-, 1961, Ser. No. 95,726 Qlaims. (Cl. 297-349) This invention relates to a movable chair. More particularly, this invention relates to a chair supported by a stationary base member, the chair being movable with respect to the base member by means of structure interconnecting the chair and the base. A more limited aspect of this invention relates to such a chair in which the base member is comprised of an elongated frame member for receiving a desk and the like, the frame member including supporting legs in association therewith.

In the past, caster constructions have been provided on the bottoms of chairs to facilitate their movement. All types of caster constructions have a number of inherent disadvantages. This is especially true in situations requiring effortless, multi-directional movement of the seat by the occupant. For example, men working on missile projects, monitoring radar screens, operating electronic computing machines and the like often require such movement when tabulating the electronic information and keeping an eye on a wide array of equipment. Frequently, the operator must move in close to the equipment or back away from it and shift from one side to the other. Chairs with caster constructions simply are not well adapted for use in such situations because rapid multi-directiona'l movement is not possible. Excessive effort must be eX- pended to rotate the casters for sudden side movement. Further, the operator cannot have precise and accurate control of his movement.

Caster constructions also exhibit other disadvantages in other environments. For example, all caster constructions subject carpeting and floor surfaces to excessive wear. This has necessitated the provision of slabs of plastic material and the like under the area over which the movable chair with casters is to traverse. This is both unsightly and expensive. Not only in the situation noted above, but in all situations a caster construction cannot provide a fluent horizontal motion for the seat. As noted above, in the present typical caster chair there is a momentary resistance in starting a horizontal movement caused by the need to force all the casters into a new direction alignment. This inherent structure eliminates the possibility of a fluid horizontal motion and contributes substantially to the wear and tear on carpeting and lioor surfaces.

It is therefore an object of this invention to provide a movable chair eliminating conventional caster constructions.

Another object of this invention is to provide a chair, operably connected to a stationary base, the chair obtaining its support solely through the base and movable by means of its connection to the base.

Another object of this invention is to provide a chair of a structure such that the occupant can attain fluent horizontal motion. 7

Another object of this invention is to provide such a chair which enables the occupant to move horizontal-1y through a wide radius with respect to its base, all movement within this radius being equally fluent.

Another object of this invention is to provide a movable chair especially well adapted for use by operators of radar screens, electronic computing machines, missile launching equipment and the like.

A still further object of this invention is to provide a movable chair which eliminates Wear and tear on carpeting and floor surfaces.

Yet another object of this invention is to provide a movable chair in combination with a desk frame, the specific unit exhibiting the objects and advantages noted hereinbefore.

These and other objects of this invention will become' obvious to those skilled in the chair art upon reading the following specification in conjunction with the accompanying drawings, wherein:

FIG. 1 is a side view of a movable chair embodying the concepts of this invention;

FIG. 2 is a side view of the chair shown in FIG. 1, the chair having been moved to the rear;

FIG. 3 is an exploded, perspective view showing the component parts of the chair of FIG. 1;

FIG. 4 is a schematic view showing two exemplary positions of the chair;

PEG. 5 is a perspective view of a chair embodying the concepts of this invention, utilizing a base structure comprising a desk frame;

FIG. 6 is a view similar to FIG. 5, the desk frame being shown in detail;

FIG. 7 is an enlarged view, showing .the interconnection of the chair to the desk frame;

FIG. 8 is a schematic view showing several positions of the chair with respect to a desk and storage unit mounted on the frame;

'FIG. 9 is a side view showing the relation of the frame extension to the floor according to one embodiment of this invention;

FIG. 10 is a perspective view of a means for locking the movable chair of this invention in position, the locking means shown in unlocked position;

FIG. 11 is a perspective view similar to FIG. 10, the locking means shown in locked position;

FiG. 12 is a cross-sectional view of another base structure for the chair of this invention, the base structure shown mounted on a level floor; and

FIG. 13 is a cross-sectional View of the base structure shown in FIG. 12, the base structure shown mounted on a tilted floor.

Briefly, this invention relates to a movable chair including a stationary base member. A first supporting arm is pivotally secured to the base member, the first arm extending in a lateral direction therefrom. A second supporting arm is pivotally secured to the free end of the first supporting arm and movable through an area extending beyond the area traversed by the first arm. A seat is rotatably secured to the free end of the second supporting arm, the base member providing the sole support for the seat through the first and second arms. In a more limited aspect of this invention, the base member includes an elongated frame member for receiving a desk and the like, the frame member including supporting legs in association therewith.

Referring more specifically to the drawings, the reference numeral 1 designates a chair embodying the concepts of this invention (FIG. 1). The chair 1 includes a base 2, a connecting structure 15 and a seat 39.

Turning to FIG. 3, the base 2 includes an attachment member 3: having a plurality of multi-directionally extending legs 4. Apertures 5 extend through the ends of each leg 4 for receiving the attachment bolts o. The attachment bolts 6 rigidly secure the attachment member 3 to the surface above which the seat 30 is to be movable. A relatively short, upstanding pin 7 extends upwardly from the attachment member 3. A cover 8, having an aperture 9 in the top thereof, fits over the pin 7 and conceals the attachment member 3 from view. A washer 1t) and a cap 11 for insertion on the top 12 of pin 7 are also provided, the purpose of which will be more fully described hereinafter.

The connecting structure in the embodiment shown,

comprises a pivoted linkage 15 including a pair of first supporting arms 16 and I7 and a pair of second supporting arms 24 and 25. Each supporting arm is preferably of a cross section such that its height is considerably greater than its width. The supporting arms may be fabricated from fiberglass with an aluminum honeycomb core. Such a structure accomplishes a torsion resistant frame with a strong lightweight fiberglass shell, increasing the beam strength and torsion resistance by means of the honeycomb core. The first supporting arm 16 includes a pair of eyelets 18 at one end thereof and the first supporting arm 17 includes a single enlarged eyelet 19 at an end thereof. It will be noted that the eyelets 18 and 19 receive the pin 7 of the base 2, thereby pivotally securing the first supporting arms 16 and 17 thereto. The free ends of first supporting arms 16 and 17 are hingedly secured toan end of the second supporting arms 24 and 25, the hinged connections being designated by the reference numerals 2t] and 21 respectively. Resilient bumpers 22 and 23 are secured to the inner faces of the first supporting arms 16 and 17 adjacent the hinged connections 20 and 21, the purpose of which will be more fully explained hereinafter. The free ends of the second supporting arms 24 and 25 are hingedly secured together, as designated by the reference numeral 25. A resilient bumper 27 is secured to one of these supporting arms adjacent the hinged connection 26. A socket 128 is provided at the remote ends of these second supporting arms,

for rotatable reception of means 31 provided at the bot- I tom of seat 30.

The movable chair 1 is assembled as follows. The attachment member 3 is affixed to the floor by means of the attachment bolts 6. The cover 8' is positioned over the attachment member 3, concealing it from view and exposing the pins 7. Eyeletsls and 19 of the first supporting arms 16 and 17 rotatably receive the pins 7. Second supporting arms 24 and 25, hingedly connected to the first supporting arms 16 and 17 by the hinged connections 20 and 21 respectively, extend laterally and upwardly from the base 2, the seat 30 being rotatably mounted at the hingedly connected ends of the second supporting arms. It will now be noted upon an examination of FIG. 1 that the seat 30 is adapted to extend a considerable distance from the base 2. As shown in FIG. 2, the seat 30 may be moved rearwardly toward the base 2, due to the hinged connecting structure and its rotatable mounting on the base 2. Further, the chair 30 may be rotated with respect to the connecting structure. In addition, the entire connecting structure may be rotated with respect to the base 2. Two exemplary positions, A and B, of theseat 30 are schematically shown in FIG. 4, clearly illustrating the adaptability of this movable chair 1 to any position with respect to its imme- (FIG. 9) although it is to be understood that the invention is not to be limited to this engagement. It should be noted that the free end 51 and at least two of the legs supporting the frame may be secured to the floor F to give greater stability. It will now be noted that a storage unit 52, including drawers 53 and a sliding door 5 may be mounted on the frame 42 above itsleg 43. A desk top is mounted on legs 48 and storage unit 52 Turning specifically to FIG. 7, the connecting structure 59 includes a first supporting arm 61 and a second above the leg 43 of the frame 4-2. supporting arm 62. These supporting arms may be of a structure similar to that of the supporting arms 16, 17, 24 and 25 described hereinbefore. The first supporting 'arm 61 is hingedly connected to the end 51 of extension 50, the hinge connection designated-by the reference numeral 63. An end of the second supporting arm 62 is hingedly connected to the. free end of the first supporting arm 61, this hinge connection designated by the reference numeral 64. A socket is provided at the free end of the second supporting arm 62, for rotatable reception of securing means 71 of seat 70.

This movable chair and desk structure is assembled as follows. Having provided the frame 42 as described, together with the storage unit 52 and the desk top 55, the connecting means 60 is pivotally secured to the end 51 of extension 59. The connection 63 hingedly secures the first supporting arm 61 to the frame. The second supporting arm 62 is hingedly connected to the first supporting arm 61 at connection '54. The seat is rotatably mounted on the free end of the second supporting arm 62. A unit is thus provided which allows complete suspended movement of the seat 70 with respect to the storage unit 52 and the desk top 55. This structure is shown by the schematic diagram of FIG. ,8. The seat 70 is shown in three of its possible positions, designated by the reference numerals A, B and C. In position A, the seat is positioned for Work at the desk. In position B, the seat is positioned for work both at the desk and the storage unit. In position C, one has complete access to the remote end of the storage. unit. Thus, fluent horizontal movement has been provided'throughout the entire working area.

In the event one wishes to lock the, seat 70 in any one fixed position, the locking means 80, shown in FIGS. 10 and 11 may be utilized. This locking means includes a pair of rods 81 and 82 movably seated Within the first supporting arm 61,-; End 33 of rod 81 is positioned addiate environment. Fluent horizontal movement is provided in any direction, the initial effort for any such movement being minimal. The occupant is aided in movement from extreme positions of the seat 30 by means of the bumpers 21, 22 and 27. Also, when the occupant rises from the chair when the seat is in an extreme position, these bumpers tend to move the chair from extreme positions for future use.

Turning to FIGS. 58, a modified base structure is disclosed, designated by the reference numeral 41. In this structure, the movable chair is designated by the reference numeral 40, including a seat 70 secured to the base 41 by means of the connecting structure 66. The base 41 includes a generally L-shaped frame 42'having the legs 43 and 44. End rails 45 and .46 are secured to the ends of the legs 43 and 44 respectively. Legs 47 are associated with the .end rail 45, and legs 48 are associated with the end rail 46, the legs 48 extending to the height of an average 'desk. Further, a' leg 49 is associated with the frame 42 generally adjacent the connection of legs 43 and 44 thereof. An extension "Bil extends from leg 43"of frame 42' and in a preferred embodimentthe free end 51 thereof [engages the. floor F jacent the end 51 of the extension 50 and end 84 of rod 82 is positionedadjacent the hinged connection 64 of the supporting arm 62 to the supporting arm 61. An eccentric member 35 is movably positioned .between the other ends of the rod 31 and 82, the lever. arm 86 operably secured to the eccentric member 85. When. the lever 86 is moved to rotate the eccentric member as shown in FIG. 11, the rods 81 and 82 are separated and bear rigidly against the end 51 of the extension 50 and the second supporting arm 62 at its pivotal connection to the first supporting rod 61. In this position, the first supporting arm 61 cannot move with respect to the extension 50 and the second supporting arm 62cannot move with respect to the first supporting armdl. Consequently, the seat 70 remains in a fixed position. By merely rotating the lever 86 back to the position shown in FIG. 10, the rods 81 and 82 no longer are held under pressure, allowing the supporting arms and the seat '70 to move freely as described hereinbefore. With this simple construction, a movable chair embodying the concepts of this invention may be rigidly locked in position.

Due to the ease of operation of the movable chairs disclosed herein, the surface on which thebase of the movablechair is affixed must be level. Since the embodiment of this movable chair'as disclosed in FIGS. 1 -4 will often be moved in mobile equipment, such as trailers, an alternaassures horizontal movement of the chair regardless of the inclination of the surface on which the base is mounted. This alternative base structure is designated generally by the reference numeral 90 (FIG. 12). The base structure 99 includes a first member 9:1 having an arcuate upper surface 92 with an enlarged opening 93 therethrough. In the embodiment shown, the first member 91 is generally circular and includes a depending wall 4 having a flange 95 extendirn outwardly therefrom. Bolts 96 extend through openings in the flange 95 for rigidly affixing the first member 91 to the surface F.

Base 95 also includes a second generally circular member 98 having a lower arcuate surface 9? adapted to slidably engage the arcuate surface 92 of the first member 91. An upstanding pipelike member 100 extends from the top surface of the second member 98, the opening 101 extending through the pipelilre member res and the body of the second member 98. A flange 1492 depends from the edge of the second member 98 and a conventional 360 degree bubble level (not shown in detail) 163 is mounted in its top surface.

A third member 1% extends through the openings 93 and tar, an enlarged portion 197 bearing against the bottom of the first member 91. Enlarged portion 197 is larger than the opening 93 in the first member 91. A lever 193 having an eccentric end 169 is pivotally secured to the top of the third member 106. It will be noted that when the lever 133 is positioned as shown in solid lines in FIG. 12, the eccentric end 1% thereof raises the third member 1% such that the enlarged end 107 thereof bears against the bottom of the first member 91, thereby rigidly securing the second member 98 therebetween, preventing relative movement of the members 91 and 98. However, if the lever 198 is raised to the position shown in dotted lines in FIG. 12, the enlarged portion 107 of the third member 166 is released from engagement of the bottom of the first member 91, thereby allowingrelative movement between the members 91 and 98.

The pivoted linkage 15 (described hereinbefore) may be rotatably mounted on the pipelike member 169 of the alternative base structure 98. As described above, when the lever 1% is in the dotted position shown in FIG. 12 the members 91 and 93 are movable one with respect to the other. The third member 196 is movable with respect to the member 91 because of its enlarged opening 93. In the event the movable chair including the pivoted linkage 15 is to be mounted in a trailer having a tilted floor or mounted on any non-horizontal surface, the members 91 and 98 are moved relative to one another until the 360 degree bubble level 1153 shows that the second member 98 is perfectly level. As shown in FIG. 13, the lever 168 is then moved downwardly, locking the second member 98 between the eccentric end 199 thereof and the first member 91. Thus, even though the floor is tilted, the chair itself is mounted for perfect horizontal movement. Thus, by merely securing the first member 91 to the tilted surface F (FIG. 13) by means of the bolts 9-5 and by positioning the second member 98 such that the bubble level 103 shows it to be p rfectly level, horizontal mounting has been achieved. This exact horizontal position is accomplished by the relative movements of the arcuate surfaces )2 and 99 with respect to one another.

It will now be understood that this invention has provided a movable chair which eliminates the use of conventional caster structures. This chair enables the occupant to move in any direction within the vicinity of the stationary base, the horizontal movement being fluent and the initial effort required to provide movement being minimal. Elimination of the momentary resistance caused by the need to force all casters in a new direction is achieved. The seat is especially well adapted for use in conjunction with complex electronic equipment and an environment equiring movement about the equipment. Further, this movable chair is especially well adapted to be used in combination with a desk or a desk and storage unit. Simplicity of design and structure is retained. Further, wear 6 and tear on carpeting and floor surfaces is virtually eliminated.

While only certain embodiments of this invention have been shown and described, it may be possible to practice this invention through the utilization of certain other embodiments without departing from the spirit and scope thereof. Such other embodiments are to be included as part of this invention unless the following claims specifically state otherwise.

I claim:

1. A movable chair, comprising: a stationary base member bolted to the floor and including a short upstanding pin; a pair of first arms each pivotally secured to said upstanding pin and extending in a lateral direction therefrom, said first arms movable through a common path; a pair of second supporting arms, one of said second arms pivotally secured to the free end of each of said first arms and movable through an area lying above the area traversed by said first arms and extending beyond the area traversed by said first arms; and a seat pivotally secured at the free ends of said second arms, said free ends of said second arms pivotally connected, said base member providing the sole support for said seat through said first and second arms.

2. A movable chair, comprising: a stationary base member; a pair of firstarms each pivotally secured to said base member and extending in a lateral direction therefrom, said first arms movable through a common path; a pair of second supporting arms, one of said second arms pivotally secured to the free end of each of said first arms and movable through an area extending beyond the area traversed by said first arms; a seat pivotally ecured at the free ends of said second arms, said free ends of said second arms pivotally connected, said base member providing the sole support for said seat through said first and second arms and resilient means secured on the inner side of one of said second arms adjacent its free end and on both of either said first or second legs adjacent their pivotal connections for biasing said seat from its extreme positions.

3. A movable chair, comprising: a stationary base member afiixed to the floor including an upstanding pin; a pair of first arms each hingedly secured to said upstanding pin and extending in a lateral direction therefrom, said first arms movable through a common path; a pair of second supporting arms, one of said second arms hingedly secured to the free end of each of said first arms and movable through an area extending beyond the area traversed by said first arms; a seat pivotally secured at the free ends of said second arms, said free ends of said second arms hingedly connected, said base member providing the sole support for said seat through said first and second arms; both said first and second arms having a cross section with a height substantially greater than its width; and resilient means secured on the inner side of one of said second arms adjacent its free end and on both of either said first or second legs adjacent their pivotal connections for biasing said seat from its extreme positions.

4. A movable chair, comprising: a stationary base member bolted to the floor and including a short upstanding pin; a pair of first armseach hingedly secured to said upstanding pin and extending in a direction upwardly and laterally therefrom, said first arms movable through a common path; a pair of second supporting arms, one of said second arms hingedly secured to the free end of each of said first arms and movable through an area lying above the area traversed by said first arms and extending beyond the area traversed by said first arms; a seat pivotally secured at the free ends of said second arms, said free ends of said second arms hingedly connected, said base member providing the sole support for said seat through said first and second arms; and both said first and second arms having a cross section with a height substantially greater than its width.

through a common path; a pair of second supporting arms, one of said second arms hingedly secured to the free end of each of said first arms and movable through an area extending above and beyond the area traversed by said first arms; a seatpivotally secured at the free ends of said second arms, said free ends of said second arms hingedly connected, said base member providing the sole support for said seat through said first and second arms; both said first and second arms having a cross section with a height substantially greater than its width; and resilient means secured on the inner side of one of said second arms adjacent'its free end and on both of either said first and second legs adjacent their pivotal connections for biasing said seat from its extreme positions.

References Cited by the Examiner UNITED STATES PATENTS 8 Hamilton 5-315 Riebe 297-240 Richardson et al. 248-282 Stuchlak 248-282 Miles 297-349 Moore 297-241 Stahl 248-240 Hultgren 297-349 V Sheldon 248-282 Parks 297326 Scheuerman et al 248-415 Hoag et a1 248-194 FOREIGN PATENTS FRANK B. SHERRY, Primary Examiner.

GEORGE L. BREHM, Examiner. 

1. A MOVABLE CHAIR, COMPRISING: A STATIONARY BASE MEMBER BOLTED TO THE FLOOR AND INCLUDING A SHORT UPSTANDING PIN; A PAIR OF FIRST ARMS EACH PIVOTALLY SECURED TO SAID UPSTANDING PIN AND EXTENDING IN A LATERAL DIRECTION THEREFROM, SAID FIRST ARMS MOVABLE THROUGH A COMMON PATH; A PAIR OF SECOND SUPPORTING ARMS, ONE OF SAID SECOND ARMS PIVOTALLY SECURED TO THE FREE END OF EACH OF SAID FIRST ARMS AND MOVABLE THROUGH AN AREA LYING ABOVE THE AREA TRAVERSED BY SAID FIRST ARMS AND EXTENDING BEYOND THE AREA TRAVERSED BY SAID FIRST ARMS, AND A SEAT PIVOTALLY SECUREE AT THE FREE ENDS OF SAID SECOND ARMS, SAID FREE ENDS OF SAID SECOND ARMS PIVOTALLY CONNECTED, SAID BASE MEMBER PROVIDING THE SOLE SUPPORT FOR SAID SEAT THROUGH SAID FIRST AND SECOND ARMS. 